Cristian Zapata was pretty beastly for me, especially paired with Vermaelen. I managed to get him for around £10m. Otherwise, you can't go wrong with any of the above mentioned. If you feel like shelling out, Gerard Pique is worth it.
id raid dortmund! subotic and hummels look a class act.... not managed them yet tho! so might be wrong.... with 90mil tho you could even look at cheillini/bocchetti